package com.lingtu.shopwxserver.utils;

import java.security.MessageDigest;

/**
 * @ClassName SHA1
 * @Description sha1 加密
 * @Author MaShuai
 * @Date 2018/11/21 10:32
 * @Version 1.0
 **/
public final class SHA1 {
    private static final char[] HEX_DIGITS = {'0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

    /**
     * @Description 把密文转换成十六进制的字符串形式
     * @Param [bytes]
     * @return java.lang.String
     */
    private static String getFormattedText(byte[] bytes) {
        int len = bytes.length;
        StringBuilder buf = new StringBuilder(len * 2);
        for (int j = 0; j < len; j++) {
            buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);
            buf.append(HEX_DIGITS[bytes[j] & 0x0f]);
        }
        return buf.toString();
    }

    /**
     * @Description 转换
     * @Param [str]
     * @return java.lang.String
     */
    public static String encode(String str) {
        if (str == null) {
            return null;
        }
        try {
            MessageDigest messageDigest = MessageDigest.getInstance("SHA1");
            messageDigest.update(str.getBytes());
            return getFormattedText(messageDigest.digest());
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

}
